A tabletop water filter demo designed to remove phosphorus from waste water has in five-years grown into a fully functional water treatment system capable of filtering more than 100-thousand gallons per day.

Designed by a small U.S. Geological Survey team, this cost-effective and environmentally friendly water filter system uses discarded mining byproducts, called mine drainage ochre, as the primary filtering agent to remove phosphorus from municipal and agricultural waste waters.

Even though phosphorus is a vital nutrient for humans, animals and crops, it can cause problems in watersheds. Dietary phosphorus that animals and humans consume is excreted into waste water, where it can accumulate and feed cyanobacteria, spawning harmful algal blooms.

Harmful algal blooms are an explosion in algae growth, and are fueled by excess nutrients in water like phosphorus and nitrogen. The blooms can cause thick mats to accumulate on the surface of water and can deplete water oxygen concentrations, creating hypoxic dead zones responsible for fish kills and shellfish deaths. Some species of algae can even create a variety of toxins that are harmful to humans and wildlife.